Acetone → 2,5-Dicarbamoylbenzoic acid

Participants

Reaction Steps

In this step, 4-carbamoylphthalimide is prepared by reacting trimellitoyl chloride with ammonia and dehydrating the obtained product. Specifically, this reaction is conducted by reacting trimellitoyl chloride with aqueous ammonia either without any solvent or in a state dissolved in a solvent at a temperature ranging from about −15° C. to room temperature. The solvent to be used in this case is preferably acetone, dichloromethane, chloroform or ethyl acetate, though any organic solvent inert to the reaction may be used. The resulting reaction mixture is treated with an acid to give a mixture comprising 2,4-dicarbamoylbenzoic acid and 2,5-dicarbamoylbenzoic acid. This mixture is further treated in the absence or presence of a solvent for 0.5 to 24 hours to give the objective compound. This treatment is conducted at room temperature to about 200° C. The solvent to be used in this treatment is preferably N-methyl-2-pyrrolidinone, though any solvent inert to the reaction may be used.

Provenance & Evidence